Form and method of casting a concrete roof



.F ,11 D. K. THOMAS 24,425

' FORM AND METHOD OF CASTING A CONCRETE ROOF Original Filed March a, 1955 2 Shets-Sheet 1 DONALD K.THoMAs,'

// 1 BY N NJ ATT RNEY D. K. THOMAS Re. 24,425 FORM AND METHOD OF CASTING A CONCRETE ROOF Feb. 4, 1958 2 Sheets-Staget 2 Original Filed March 3, 1955 lL/s lNvENT OR DONALD K. THOMAS,

ATTORNEY original patent but forms no part of this reissue United States Patent Ofiice Re. 24,425 Reissued Feb. 4, 1958 FORM AND METHOD OF CASTING A CONCRETE ROOF Donald K. Thomas, West Hollywood, Fla.

3 Claims. (Cl. 25118) Matter enclosed in heavy brackets appears in the specification; matter printed in italics indicates the additions made by reissue.

This invention relates to roof constructions and primarily to novel form means whereby the roof may be poured into an integral stepped slab.

The invention contemplates novel form devices that are supported upon the roof in a manner whereby a concrete mix may be poured to form the concrete mix flowing beneath the form devices to assume a predetermined angularity with respect to the roof and with the form devices being subsequently removed to present a novel integral stepped roof.

Various features of construction and operation of the device will be clearly apparent during the course of the following description, reference being had to the accompanying drawings, wherein has been illustrated the preferred forms of the device and wherein like characters of reference are employed to denote like parts throughout the several figures.

In the drawings:

Figure 1 is a top plan view of a roof and with the form devices of this invention supported thereon preparatory to completing the roof,

Figure 2 is a sectional view illustrating the manner of mounting and supporting the form devices preparatory to pouring the slab,

Figure 3 is a fragmentary perspective view on an enlarged scale illustrating the form devices supported in position upon the roof and illustrating a means for tying the several form devices together against shifting,

Figure 4 is a fragmentary section illustrating a completed roof slab,

- Figure 5 is a fragmentary side elevation of one form device,

Figure 6 is a fragmentary perspective view of a modified form of form device and its supporting means,

Figure 7 is a section taken substantially on line 7-7 of Figure 6, and I Figure 8 is a transverse section through a modified form of the'form device.

Referring specifically to the drawings, the numeral 5 designates a conventional roof embodying rafters 6, sheathing 7 and a layer of building paper 8. The marginal edge of the roof is provided with the usual flashing strip 9, nailed or otherwise attached to the edge of the sheathing 7 and with its upper flange underlying the marginal portion of the paper 8, as is customary. It is contemplated that substantially an entire roof shall be poured at one operation and where possible in a conventional roof design a plurality of form strips 10 are arranged in parallel relation over the building paper 8. One conventional arrangemeut of the strips 10 is shown in Figure 1 where a hip type of roof has been illustrated and wherein the strips 10 are disposed longitudinally of each roof area and with the strips of the end portions of the roof having abutting and overlapping engagement with the strips upon the longitudinal portions of the roof whereby to effect a plurality of continuous channels entirely over and around the complete area of the roof. Temporarily connected over the flashing 9 and substantially flush with the paper covering 8 is a spacer strip 11. The strip 11 is of a width corresponding to the degree of overhang of the concrete slab to be-poured. Fixed to the strip 11 is a facia board 12 that projects-above the strip 11 a distance corresponding to the maximum thickness of the slab. The strip 11 and the board 12 will be subsequently removed after the slab has been poured and suitably cured and the board 12 constitutes the supporting means for the several strips 10 whereby to hold the strips 10 in a predetermined parallel and spaced apart relation. Each strip 10 is provided at spaced apart points with legs 13 that normally rest upon the surface of the paper 8 and with the combined height of the strip 10 and the legs 13 being substantially identical to the height of the board 12 above the strip 11. Any suitable mesh wire reinforcing 14 is first disposed over the paper 8 to be embedded within the slab to be poured. Since the board 12 presents a face that is at right angle to the surface of the roof, it is essential that the several strips 10 be supported in a corresponding position. For this purpose, there has been provided a plurality of straps 15 formed of either wood or metal, and these straps 15 are apertured at predetermined points corresponding to the spacing of the strips 10. The straps 15 are nailed or otherwise connected with the board 12 and the several parallel strips 10 in each group whereby to maintain the strips in a predetermined angularity and spacing against shifting, and with the lower edge of the strips 10 being in spaced relation to the paper 8 that is dimensioned to correspond to the minimum thickness of the stepped portions of the slab to be poured. The legs 13 may, if desired, rest upon small metal discs or the like (not shown) whereby to avoid piercing the paper 8.

Now with the several form strips in supported relation upon the roof area, the operator proceeds to pour a concret mix in the uppermost channel formed by the strips and, as the mix is continued downwardly, it will'flow beneath the lower edges of the strips 10 and around the legs 13 to the top of the next lower adjacent strip 10. As each channel is filled with the concrete mix, a suitable trowel, such as that illustrated in Figure 3 and designated by the numeral 16, is troweled over the surface to impart a smooth finish to that particular stepped portion of the slab. The trowel 16 has a length sufficient to extend from one strip 10 to another whereby it is jointly supported upon two adjacent strips. The trowel 16 is angled upwardly, as at 17, and outwardly, as at 18, whereby to form a rest that is shifted by the operator along the form strip. The angled portion 17 terminates at the lower edge, of the strip 10, while its tail portion 19 overlies the next adjacent strip. Thus, the concrete is troweled from the top of one strip downwardly to the bottom of the next upper strip. The procedure the roof down to the facia board 12, in each instance the successive stepped portions being troweled to a smooth surface. As the concrete is poured into the forms, it obviously embeds the mesh 14 whereby to impart sufiicient strength to the slab against cracking. After the concrete has set asutficient length of time, the straps 15 are removed and the several form strips 10 are lifted upwardly, pulling their legs 13 outwardly from the slab,

concrete in uniform stepped sections. The openings left is continued over the entire area of by .thenlegs. ,13, are ..subsequeutly pointed. up with cement-- pouring the rest of theslab.

InFigure 6 therehas been illustrated a slightly modified forrntof form strips -10,-here shown as being formed "of angle iron21 having the :proper height corresponding to the. height of the stepitobeformed. The lower'edge of the. angleiron 21is provided with the supporting-legal A connecting strap 2'3,"-corresponding toithe strap15, is preferably formed of'metal,

corresponding tothe legs 13.

andthisstrap 23 is provide'd with a'plurality ofslots 24for the passage of hook bolts-ZS -carryingpreferably wing nuts: 26.

the: several forms may be rigidly held in theirspacedparallel relation. tially identical to that first In Figure 8 there has been illustrated a further modified form of form strip.27, here illustrated as having one facegrooved and under-cut, as at 28,- for 'thereception of a hook .bolt 29 passing through a strap 30, similar-to the strap 23. The form 27 alsocarries whereby'thexform is spaced above the roof a predeter minedtdistance corresponding to the minimum thickness of theslab at the point of stepping.

It will be apparent. from the foregoing that avery' simple and novel form has been provided whereby an operator may completely pour an integral stepped concrete 1 and with a minimum of effort and time in installing the forms and their subsequent removal. The forms areof such nature as will readily permit them tobe assembled roof uponnumerous roofs ofwarying sizes and-with the terminal ends of the strips being overlapping andin abutment whereby to minimize the number of forms necessary and totavoid the necessity of cutting theforms for aparticular roof. The supporting strapslS, 21 and 30 greatly facilitate the :supporting of theforms in anaccurately spaced Th'e several:- partsr-are' extremely simple in construction, are strong; cheap to'manufacture and have'a relatively'long life andtparallel manner in a minimum of time;

since-they may be used over and over, thus greatly reducing the cost of installing an integral stepped roof slab.

Itis to'bc understood that the invention is not limited to the precise structural details illustrated but that changes are-"contemplated as readily claims;-

Having' described my invention; what I clairmas new andfdesire to secure by'Letters Patent is:

1; A -form for 'pouring-a'one-piece concrete roof slab and whereinthe form constitutes'longitudinally extending troughs-the form embodying a plurality of substantially identical-form devices having fiat sides and with an upper edge of eachform legs formed upon and'proje'cting'thereabove and a pluralityof straps con nected with the facia each-of the straps being provided with spaced longitudinal indicated. at 20 'in I dotted "linesdn Figure 2, is fir'sttformed upon the ridge of the rooftpreparatory to In use, afacia boardand a spacer strip are employed asbefore, afterwhich theseveral form elements 21 rarexarrangedupon the roof and engaged-by the hook bolts-:25 in a manner shown clearly :in Figure 7 whereby The operation of this device is-substa'ndescribed as to arrangementupon the roof for its complete-area, the pouring of the' concrete mix and the subsequent removal ofthe forms.-

the spacing legs 31v fall within the spirit'of the invention as determined by the scope *of the 'subjoined device being at a right angle,- spacing the lower edge of each form device whereby to support the form with its lower edge in spacedparallelrelation :to a roof surface to be covered, a faciaboard detachably connected with'the free edge of the roof board and-with the form: devices,

slots and hook bolts that engage through-the slots and have hooked and clamping engagement with angled upper edges of the form devices whereby the several form devices are adjustably held aha-predetermined angularity with respectrto the roof surface/to becoveredand in a predetermined spaced parallel relation to each other and to the facia board.

2. The t hereindescribed method. offorming an integral steppediconcretetroof slab over the entire .area .ofra roof; and wherein-the roof embodies :aridge and .aplurality of inclined and connecting' roofsections,- that comprisessupporting a plurality of form strips longitudinally of each roof section and :w-itlr the strips 'being'in spaced parallel relation toeach other ,to constitute troughs; the strips :of connecting sections overlying and-abutting theendsioftthes;

strips of the adjacent sectionstwherebywthe troughs extend: entirely around the roof, the lower edges ofeach strip being in spaced relation to the root surface, facia boards that: are-connected-to-the free edges of eachroof'section, connecting straps'fastened'tothe facia boards of eachs'ec-" tion and that are connected 10*.(116 sever-alfo'rm stri'psof next lower fo'rmstrip whereby to -form*stepped' portions" having amaximum thicknesszcorrespondingto the height oflone form' strip and a minimum thicknesscorresponding 5 to'ithe lower edge-of. the next adjacent- 'strip-andthen-re moving the several form strips-and-the facia-boards aftertheconcrete has hardened.

3. The hereindescrz'bed method of forming awintegr al stepped concrete roof slab 'over the entire-area of-'a roof and wherein -the r00f embodies a ridge and rt-plurality of inclined and connecting roof sections, that comprises-sup porting-d plurality of formstripslongitudinally" of jeachi roof section: and with the strips being spaced paralle l relation to each T orhemo constitute troughs; the strips'of connecting sections overlying and abutting the *ends of the strips of the ad acent sections whereby theiroughs extend entirely' around the roof, the lower edges of each-strip being'in' spaced-relationto the roof surface; facia boards that are connected to the free edges of'each'roofsectidn; the concrete" being-poured into the -=uppermosttrough"'to flow. beneath thalow'er edge' of the adjiz'cent 'fdrmaforprogressively filling the troughs to the top'edge of'u nextlower adjacent form strip"; trowelling L the poured concrete from the lower edge of one-form strip to the to'p edge-0fthe next. lower form stripwhereby =t0' form stepped "partions havingamaximum thickness corresponding to the height 09 one form=strip and a'minimum thicknesscarresponding to the lower edge of the next adjacent-strip and:-

then removingth several form strips and the 'fa'cia' boards after the concrete has hardened.

References Cited in the file of this patent i or, the original patent,

UNITED STATES PATENTS thetopedge of a next lower 

